Discovery of novel benzimidazole resistance mechanisms

发现新的苯并咪唑耐药机制

• 批准号: 10438771
• 负责人: Erik Christian Andersen
• 金额: $ 68.21万
• 依托单位: NORTHWESTERN UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-07-01 至 2023-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10438771
• 关键词: Affect; Albendazole; Alleles; Anthelmintics; Biological Assay; CRISPR/Cas technology; Caenorhabditis elegans; Collaborations; Communities; Drug Design; Drug Targeting; Early Diagnosis; Economic Burden; Enzymes; Evolution; Farm; Future; Generations; Genes; Genetic; Genetic Crosses; Genome; Genomics; Goals; Growth; Haemonchus; Helminths; Hookworms; Human; Knowledge; Laboratories; Longevity; Measures; Medicine; Modeling; Molecular; Monitor; Morbidity - disease rate; Nematoda; Oxides; Parasite resistance; Parasites; Parasitic nematode; Persons; Pharmaceutical Preparations; Phenotype; Phylogenetic Analysis; Poisoning; Population; Production; Proteins; Research; Research Personnel; Resistance; Resources; Ruminants; Sampling; Soil; Structural Biologist; Testing; Time; Tissues; Transgenic Animals; Translating; Veterinary Medicine; X Chromosome; base; benzimidazole; benzimidazole resistance; beta Tubulin; disability-adjusted life years; experimental study; fitness; fitness test; follow-up; gamma Tubulin; gene discovery; genetic approach; genome editing; genome-wide; health economics; mortality; novel; offspring; pathogen; programs; resistance allele; resistance gene; resistance mechanism; success

Project summary: Parasitic nematodes impose a massive health and economic burden across much of the developing world, infecting over one billion people worldwide. The morbidity and mortality inflicted by these devastating pathogens is partly curtailed by mass drug administration (MDA) programs that depend on the continued efficacy of a limited portfolio of anthelmintic drugs. Benzimidazole (BZ) compounds are a widely used class of broad-spectrum anthelmintics that are an indispensable component of this limited chemotherapeutic arsenal. The prospects of BZ resistance pose a serious threat to the future success of nematode control programs. These prospects have been realized in the veterinary domain following intensive BZ use and are predicted to materialize in human medicine with increased selection caused by expanded MDA. Early detection of resistance-associated alleles in nematode parasite populations is essential to the goal of slowing anthelmintic resistance and extending the lifespan of this critical drug class. Based on research in the free-living nematode Caenorhabditis elegans from thirty years ago, parasitic nematode researchers focus on one BZ target, a nematode-specific beta-tubulin. Despite this knowledge, it is still a complete mystery (1) whether any alleles cause resistance (i.e. go beyond correlation), (2) the nematode tissues that are sensitive to BZ poisoning, and (3) the drug-target interactions that cause resistance. In Haemonchus contortus, we have collected both validated sensitive and resistance samples, and longitudinal samples where resistance has developed over time. These samples are not available in any human parasitic nematode species. Using quantitative resistance assays on these resources, we have shown that BZ resistance goes well beyond this single beta- tubulin target. However, we do not know these independent resistance mechanisms in C. elegans or parasite species. In Aim 1, we will test explicitly whether alleles correlated with resistance in parasites actually cause resistance, test the fitness effects of these alleles, identify the tissues targeted by BZ, and characterize the molecular mechanism for how beta-tubulin in affected by benzimidazoles. In Aim 2, we will discover beta- tubulin independent mechanisms of resistance using the tractable C. elegans model nematode. In Aim 3, we will expand our results to H. contortus where genomic and validated strain resources enable discoveries of conserved resistance mechanisms. It is not possible in any parasitic nematode species to accomplish these goals. New discoveries are possible only through this interplay between the model nematode C. elegans and the tractable veterinary parasitic nematode H. contortus. Our results will have direct impacts on how treatments are administered and resistance is monitored in human parasitic nematodes.

项目摘要： 寄生线虫在整个发展中国家的大部分地区施加了巨大的健康和经济负担， 全世界感染超过十亿人。这些毁灭性的发病率和死亡率 病原体部分受到大众药物管理局（MDA）计划的限制，依赖于继续 驱虫药有限投资组合的功效。苯咪唑（BZ）化合物是一类广泛使用的类 广谱驱虫药是这种有限的化学治疗武器库中必不可少的组成部分。 BZ抵抗的前景对线虫控制计划的未来成功构成了严重威胁。 在大量BZ使用后，这些前景已在兽医领域中实现，预计 在人类医学中实现，由MDA扩展引起的选择增加。早期检测 线虫寄生虫种群中与抗性相关的等位基因对减慢驱虫的目标至关重要 阻力并延长此关键药物类别的寿命。基于自由生命线虫的研究 三十年前的秀丽隐杆线虫，寄生线虫研究人员专注于一个Bz目标，一个 线虫特异性β-微管蛋白。尽管有这些知识，但它仍然是一个完全的谜（1）是否有任何等位基因 引起抗性（即超出相关性），（2）对BZ中毒敏感的线虫组织 （3）引起抗药性的药物目标相互作用。在Haemonchus contortus，我们都收集了 经过验证的敏感和电阻样本以及纵向样品，其中电阻已经发展出来 时间。这些样品在任何人类寄生线虫物种中都不可用。使用定量 对这些资源的抵抗测定，我们已经表明，BZ抗性远远超出了这种单一的β- 微管蛋白靶标。但是，我们不知道秀丽隐杆线虫或寄生虫中的这些独立的抗性机制 物种。在AIM 1中，我们将明确测试等位基因是否与寄生虫中的抗性相关 电阻，测试这些等位基因的适应性效应，识别由BZ靶向的组织，并表征 β-微管蛋白如何受到苯甲酰唑影响的分子机制。在AIM 2中，我们会发现β- 使用可拖动的秀丽隐杆线虫模型线虫的抗药性机理。在AIM 3中，我们 将我们的结果扩展到基因组和验证的应变资源的H. totortus的发现 保守的抵抗机制。在任何寄生线虫物种中都不可能完成这些 目标。只有通过模型线虫秀丽隐杆线虫和 可处理的兽医寄生线虫H. contortus。我们的结果将直接影响 给予治疗，并在人类寄生线虫中监测耐药性。